The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Tubular mechanical link rods, i.e., with a hollow body, are in particular used in fields where there is a constant concern for saving weight.
These fields in particular include aeronautics: tubular mechanical link rods are for example used in landing gear (brake bar), systems for keeping the maintenance cowls in the open position (motor cowl, etc.), engine suspension systems (interface transmitting thrust between the engine and the mast of the wing), etc.
A tubular mechanical link rod is traditionally made up of a hollow body, including a connecting end at each of its ends.
Each connecting end is typically configured in the form of a male or female clevis, so as to allow the link rod to be fastened using a pin or any other means to the members with which it must cooperate.
Known from the state of the art, and in particular from EP 1,870,196, is a method for manufacturing a tubular link rod in which the hollow body of the link rod on the one hand, and the two connecting ends of the link rod on the other hand, are manufactured separately, then those connecting ends are attached to each of the ends of the hollow body, by welding.
The drawback of this prior method lies in the fact that welding operations must be carried out in two separate locations of the link rod.
Furthermore, with this earlier design, it is not possible to inspect or machine the parts of the weld seams that emerge inside the hollow body of the link rod, due to their enclosure inside the volume defined by the hollow body.
The geometric accident resulting from the lower part of the toe of the weld seam also causes a local stress concentration that requires that the area to be welded be thickened locally.
Consequently, it is necessary to provide a local overthickness (at the assembly zones) of the metal alloy (typically nickel-, titanium-, or aluminum-based) making up the link rod. The excess weight related thereto is therefore doubled when two welds are present.
To resolve the latter drawback, it has been considered to produce a single weld with two connecting rod halves each incorporating their respective connecting ends, each half being formed in a single piece: this solution, described in EP 0,839,593, in fact enables an overall weight reduction of the link rod relative to a link rod with two welds, but does not resolve the problem of the inspection and machining of the inner portion of the weld seam.